Deep in Black Canyon, submerged for more than 70 years, lies the site of the Low Level Water Treating Plant for Hoover Dam. It is also called the Water Towers. At this site, water was pumped from the Colorado River into a 280,000 gallon 50’x20’ Dorr clarifier where the silt was settled out. Water would then flow by gravity to a 125,000 gallon tank situated at Lomix, where it was used for concrete production. The clarifier was removed from this site prior to the filling of Lake Mead in 1935, but the concrete and wood structures remain intact and in pristine condition. There are 4 large obelisk shaped pillars that flanked the sides of the large clarification tank. These rise from the powdery bottom of the plateau like sentries guarding the Water Plant’s ruins. A grid work of lumber, which provided a level surface for the tanks, remains amazingly intact to this day. Technical dive details: What a fantastic dive! Like every dive in Black Canyon, a trip down the canyon wall is like going back in time. This is a trimix technical dive only, and proper training and experience is a must. Black Canyon can have rough water due to boat traffic, so be sure to leave yourself ample time to safely anchor your vessel. Plan your air accordingly, and bring quality lighting - This is a deep, dark, and potentially dangerous dive.http://www.missionscuba.com/lake-mead/lake-mead-dive_low-level-water-treating-plant.htm